Posted
by
Zonkon Sunday April 02, 2006 @03:40AM
from the i-call-my-tumor-tummy dept.

dtjohnson writes "A new Swedish
study has
found that heavy users of cell phones had a 240 percent increase in
brain tumors on the side of their head that the phone was used
on. The study defined 'heavy' use as more than 2,000 total hours,
or approximately one hour of use per workday for 10 years. An
earlier British
study was previously discussed
here that didn't find an increased risk, although that study
covered fewer subjects and only followed one type of brain tumor for a
shorter period of time. Or course, the biggest epidemiological
study of all is the one we are all participating in whenever we use our
cell phone. The results from that study won't be available for a
while."

Don't know if you're joking or not, but even in the summary it is mentioned the British article which goes against this, so no, we didn't "know" this 20 years ago. Hell, we still don't KNOW that it causes tumours either. What's significant about this study is the timespan of it.

Kjell Mild, who led the study, said the figures meant that heavy users of mobile phones, for instance of who make mobile phone calls for 2,000 hours or more in their life, had a 240 percent increased risk for a malignant tumor on the side of the head the phone is used.
"The way to get the risk down is to use hands-free," he told Reuters.

How does he know that? Did his study make that conclusion? The article doesn't say anything about use of hands free kits beyond that statement.

I think Mr Mild is making assumptions about the reason for the apparent 240% increase, and factors which he thinks may be important.

This article is poor (I would say unethical) coverage of a scientific study.

For example, to say something is associate with a 240% increase in risk can be technically accurate, but horribly misleading to most readers. If one in a billion people get a disease, a 240% increase makes your chance of getting it 2.4/1000000000. That is absolutely nothing to worry about.

Also, with this studay, they found out people who had tumors, then asked them if they used cell phones. The subjects probably had no doubt as to why this question was being asked, therefore this was not really a double blind experiment.

Has anyone ever been able to give a rat cancer by blasting it with amplified cellphone-type radiation? That would convince me of the possibility of cell phone risk much more than digging backward through statistical inormation does.

Another problem with a lot of these studies is that they use the other side of the brain as a control. You're supposed to get tumors more often on the side of your head you use the phone on. How consistent are people always using it on the same side?

Not to mention I suspect the people who used cell phones extensively twenty years ago are probably a very special group... probably with all kinds of interesting common factors.

"There's got to be some long term damage to putting a radio transmitter which radiates electromagnetic energy right beside your head."

Why? As has been repeated ad nauseam whenever this debate comes about, the frequencies used by cell phones are non-activating. If holding a tiny, low-power transmitter next to your head causes cancer, then people who work at TV and FM stations should be dropping like flies.

All we know at this point (assuming the study's methodolgy holds water) is that there is a correlation between cell phone use and brain tumors. It could mean that cell phones cause brain tumors, it could mean that people prone to brain tumors talk on the phone a lot.

And even if it is eventually shown that cell phones cause brain tumors, that still doesn't necessarily mean it is the radio transciever aspect of the phone that is the culprit. It very well may be exposure to toxic chemicals used in the displays or the batteries, for example, much the same way toxic pesticides used around electrical pylons had people thinking high-voltage lines caused cancer.

If the incidence is so low that you can't do a study to demonstrate it properly then we've got FAR more important things to worry about. I bet your increased risk of getting hit by a bus because you're talking on your stupid phone instead of paying attention is more significant.

Actually, that is right. But you can understand if you study a little. Which is a more controlled study, particle physics experiments or experiments done on groups of people? It's a no-brainer. Years ago they tried to scare us about power lines, only to find out the guy fudged [ncpa.org] his data. So 100's of studies say no, and one more crackpot says "Hey... here's a link!!" and now we should all start running. The nice thing about science is the results are repeatable; I can go check for myself. I have checked e-m radiation theory and it checks out.

Some brief googling reveals very little about the study discussed in this article; the closest it comes to is a compilation of several different studies.
Link to the former-pdf, now HTML-ized Google cache of the study from the original site, in both Swedish and English: Here. [72.14.203.104]

Even a cursory look at the linked study will show that there have been many, many studies on the effects of RF on animals with conflicting, confusing, and uncertain results. Unfortunately, I'm not a scientist specializing in this field, so I really can't comment one way or the other on the validity of the tests.

It's difficult not to hand-wave this study away without some real, significant, reproduceable results.

An increase from 1 person to 2.4 people getting cancer is serious, if your sample size is 10 people. If your sample size is 10,000 people, or 50,000 people, the difference between 1 and 2.4 is statistical error. To really derive anything further, we'd have to go read the study.

The trouble with doing scientific studies on real, moving people is that it's exceptionally difficult to control external variables. For instance: GSM cell phones (Cingular, T-Mobile, a few minor regional carriers) have a total of four bands they operate on, 850, 900, 1800 and another band that escapes me. CDMA phones (Verizon, Sprint, etc) operate on others, and iDen (Nextel, Southern LINC, etc) phones operate on yet another. Each type varies in wavelength and power output, so it's a vast generalization to say "Cell phones are bad for your brains", because of the vast differences between the services, the cell phones, and the effects of different frequencies on different parts of your brain.

Random appeal to authority: I'm a ham radio operator, and they make us learn interesting things about what too much RF does to you. But at the frequencies we operate, site surveys start being required when you're pushing more than 50 watts at 146 MHz (for instance). 50 watts is something like 50-100 times the amount of power that cell phones push, but, again, at different frequencies, so I'm not really sure I said anything relevant there. It's just hard to tell.

By the time the studies start showing reproduceable evidence, I'll be out of college and far away from the wireless industry, hopefully reducing my chances of being sued;)

Potentially true! But, like the tobacconist, I don't hold a gun to anyone's head and make them buy a cell phone. If they wanna rot their brain / not, or rot their lungs / not, it's entirely up to them. I just profit.;)

However, the power from a domestic light bulb in that band is? and the SUn's radiation is massively greeater

Can you provide some references for the claims you're making here (that incandescent light bulbs and the sun both output significant amounts of radiation on the same frequencies as cell phones)? It's seems unlikely - neither cause obvious interferrence with cell phones, which I'd expect if the power levels are remotely similar.

Some phones put so much RF into the hands free kit that radiation exposure is worse on hands free

Riiight... If you can make the GHz RF radiation travel into the wire of your earpiece, then you should patent it quickly, because then you've managed to do something that no radio engineer deemed possible... There's something called matching impedance you might want to investigate.

No it wouldn't.
The incidence of brain tumours are so low that even a doubling in the risk would not pose a significant risk to the general population. There are far more severe health issues related to pollution that doesn't receive a fraction of this attention. Cell phones are new ( and hence scary ) which is why we get all this media attention and poor articles about their risks.

I read the PDF detailing the study and there are a couple of gaping holes in this whole thing.

First off, despite multiple studies done that prove no correlation between brain tumours and mobile phones this claims to have found something. Now I guess other factors may have come in to those other studies some bias etc. However, this article details an initial study that also showed _no_ connection. It was only after they altered the questionaires and retested people that they found something. Whats more, they then did no further alteration to the questions and simply ran with the same test only on a bigger scale.

There may be a detailed explanation of why that occured but with currently released information weve no idea how many times they were willing to alter the questions to get the answers they wanted, and no explanation of which questions were altered or why. What adds to the suspicion is the fact that the only reason the first test was thrown out was 'short latency' and 'low numbers' of people. Neither of which affect the questionaire.

So what we have is a group of people who rely on getting a result for there funding. (No differently to the previous studies.) After they got no real results from a first test, altered it in a way that appeared to have no bearing on that initial test. They then found they got results... Doesnt really inspire any confidence in there impartial testing.

Secondly, something others have pointed out already, asking a bunch of people with tumours when they started using mobile phones and then roughly getting rid of other factors that could have caused them based on a questionaire... Not a great method of working this out.

Whatever you thought of the study seen on the BBC site it raised a very good point about something that would cause a bias. 'reporting from brain tumour sufferers who knew what side of the head their tumours were on.' etc. This test doesnt even begin to try clamp down on these kinds of bias. Even if this test was entirely fair, the results are far from dramatic. With excessive use it shows only a relatively small increase in cases. With a potential for people to be increasingly suspicious of there mobiles the more they use them this could easily be put down to false assumptions.

As far as im concerned this study is severly flawed. The other studies are also flawed, to a degree, but until someone actually has decent evidence that these things are causing damage then its not going to stop the millions of people who use them. I certainly wouldnt say mobile phones are safe but there is still little to no evidence suggesting they harm us. (and arguably more evidence to suggest that they dont.) The presure is definately on those who have to prove a link.

Suppose the risk of getting lung cancer is very small. So small, in fact, that you are much more likely to die of a heart attack or in a traffic accident than to get lung cancer. Then a study finds that smoking TRIPLES your risk of this cancer. So all the smokers out there now have a 3*(very small) == small risk. You are still more likely to die in a traffic accident.

You seem to think that this very small risk is something that can be overlooked. However, I could point a few million people who believe otherwise.

I think you see where I'm heading - while it's true that there are higher risks than the one mentioned here (or in the article), the whole point is that these are risks that we can easily avoid. And the increase in relative risk has nothing to do with the actual incidence of the disease in the studied population.

Incidentally, this "there are worse things to die of" argument was -and still is- used by a lot of smokers. Not that I would compare using cell phones to smoking (there is still too little data concerning the risks -or lack of them- associated with cellphones), but it is interesting to see how the human mind tends to follow certain patterns...

And how would you explain that the tumors were more likely to be located on the side of the head closest to where the user would put the phone?

Well, if it is unrelated, that would be easy to prove. What side of the brain are most tumors found? Or is it equal on both? What side of the head do most people hold the cell phone on? I know I use phones mainly with my right-hand/ear, so preferences do exist. If there is an unrelated propensity for right-brain tumors and right-hand cell usage, then the causation implied with the correlation is flawed. There is rarely a "cause" found for things in these types of scientific studies, just correlations explored.

And, of course, the study wasn't double-blind. I didn't RTFA, but if they found people that were diagnosed with cancer, then asked them questions, it would be human nature to assume the answer and change their answer to match the expected answer. No, this isn't lying, it's an actual subconscious alteration of perceptions, like the placebo effect. Tell someone they have cancer in their left hemisphere and ask them if they usually use the cell phone on that side, and they will be more likely to answer that they do. So, the only way to fix that problem is to lie to the patient about their disease (usually unethical) in order to remove that bias. Since that's impractical, these studies will forever be flawed. Or, we could study 1,000,000 people for 20 years and get a reasonably accurate answer to the question.

If you read the study (and know anything about experimental design) you will see that the "results" aren't nearly so impressive as they claim. The short of it: they looked at a bunch of people who already had brain cancer, and then determined how many of them used a cell phone (roughly) an hour per day. I don't know about you, but most people I know use cell phones that often on average, and so it comes as no suprise to me that approx. 85% of the people in the study had high cell phone use. What this shows is ALMOST NOTHING because it doesn't compare what the rate of high cell phone use is among the general population. All it proves is that in a group of people who had brain cancer a lot of them used cell phones. In case it seems like I'm talking circularly, think of this analogous example: if I took a group of people with brain cancer and surveyed them we would probably find that a very high percentage of them (1) drink coffee every day (2) watch television every day (3) breath air every day, but you wouldn't immediately say "OMG, [Coffee, TV, Breathing] causes brain cancer!" Anyone who believed this story without at least reading a description of the study should stop breathing now so that they don't get cancer.

No, the argument applies equally well to public health. Better in fact. If the rate is so tiny then public health money and attention is FAR better spent on other areas.

For example, should we introduce new regulations on cell phones that force cell companies to build twice as many towers which will statistically save ten lives over the next twenty years or use the same amount of money to introduce subsidized prostate and breast cancer screening programs that will statistically save a thousand lives per year?

Public health is all about the economics. You put your money where it will do the most good. Not that any of these studies are actually conclusive enough to justify anything.

Thanks for the link to the study. For the record I am a 2nd year medical student, have taken (and passed!) coursework on epidemiology, and have been published as first author in a reputable journal, the point being that I am a bit more qualified than Joe Sixpack to comment on the study. Reply to this post if you want a link to my study, but be warned that it is of limited general interest (cardiology).

First off, in response to another poster in this thread, the choice of controls is correct. In case control studies you look at groups with and without an outcome, in this study various brain tumors, and then examine whether the rate of exposure, cell or cordless usage here, differs between the two groups. Having other cancers is an entirely different outcome, and case control studies do not allow one to examine multiple outcomes by definition. A cohort study would allow for examination of multiple outcomes, but is inappropriate here since the incidence of brain tumors is so low as to make a cohort study prohibitively large and expensive.

Second, from reading the actual study as opposed to the news summaries I believe the results to be valid. Why? The results meet many criteria for causality and are strong statistically. Read on for what I mean by this.

The case for causality: First off there is biologic plausibility. Read the second full paragraph on page 9 of the pdf for discussion of this issue by the authors. Incidentally the assertion by other posters that these results are invalid because they show roughly similar odds ratios for analog, digital, and cordless phones is addressed and shown to be untrue in the first full paragraph on page 9 (as well as in the discussion of frequencies used in the introduction).

Next there is a clear dose-response relationship, as the odds ratio increases with greater cumulative wireless phone usage. This also partly addresses the issue of temporal relationship, as long term cell phone usage would necessarily predate the onset of recently diagnosed tumors.

Finally, the results seem statistically sound. By this I mean that the 95% confidence intervals do not cross 1.0, and that the relationship between exposure and outcome persists after correction for age and socioeconomic class. (Sex wasn't corrected for since the controls were already matched by the study design.)

Does this mean that I'm going to immediately stop using my cell phone? No. However, I'm going to keep on using it because I value its convenience more than the possibility of developing brain cancer at some multiple of a low rate.